In this paper I trace the development of one of the central debates of late twentieth-century moral philosophy—the debate between realism and what Rawls called “constructivism.” Realism, I argue, is a reactive position that arises in response to almost every attempt to give a substantive explanation of morality. It results from the realist’s belief that such explanations inevitably reduce moral phenomena to natural phenomena. I trace this belief, and the essence of realism, to a view about the nature of concepts—that it is the function of all concepts to describe reality. Constructivism may be understood as the alternative view that a normative concept refers schematically to the solution to a practical problem. A constructivist account of a concept, unlike a traditional analysis, is an attemptto work out the solution to that problem. I explain how the philosophies of Kant and Rawls can be understood on this model.

Although John Rawls’ A Theory of Justice does not deal specifically with the ethics of environmental concerns, it can generally be applied to give justification for the prudent and continent use of our natural resources. The argument takes two forms: one dealing with the immediate effects of environmental impact and the other, delayed effects. Immediate effects, which impact the present society, should besubject to environmental controls because they affect health and opportunity, social primary goods to be dispensed by society. Delayed environmental impacts, affecting future generations, are also subject to control because future generations have a just claim upon our natural resources-the generation to which a person belongs is an arbitrary contingency which should not exclude persons not yet born from consideration in the original contract of society.

In The Frontiers of Justice, Martha Nussbaum argues that social contract theory cannot accommodate political duties to animals because it requires the parties to the contract to enjoy rough physical and mental equality. Her interpretation of the social contract tradi­tion is unpersuasive; social contract theory requires only that the parties be equally free and deserving of moral consideration. Moreover, social contract theory is superior to her capabilities approach in that it allows us to limit the scope of the community of justice to animals we are capable of recognizing as subjects of justice and with whom we have a political relationship.

Just over seventy years ago, three trials took place in Nuremberg, Germany. At the time, they seemed a turning point in international relations—and, indeed, proved to be. The trials involved the prosecution of prominent members of the political, military, economic, and judicial leadership of Nazi Germany, those who planned, oversaw, or otherwise participated in the Holocaust and other large crimes. At the time, the Trials were widely condemned for using retroactive criminal statutes. The most famous discussion is what became known as the Hart-Fuller Debate. This paper argues that Locke provides the best account of the lawfulness of the Trials—at least when compared to the accounts offered by Fuller, Hart, and Ronald Dworkin.